1. Field of the Invention
This invention relates generally to flexible hose couplings. More particularly, it relates to a novel and improved quick connect hose coupling. Specifically, it relates to an improved high-pressure push-to-connect and threaded disconnect flexible hose coupling.
2. Description of the Prior Art
Quick connect couplings are known. In such couplings a body assembly or fixture portion may be pre-assembled on associated fixtures, machinery or equipment. The hose connection portion, including a hose stem portion and a ferrule, are attached to an open end of the hose to be connected to the fixture, machinery or equipment. The hose stem portion has a hose insert portion, which is inserted into the open end of the hose. The ferrule is then compressed about the hose end containing the insert causing all portions to be permanently affixed. Merely pressing the hose connection portion into the body assembly or fixture portion subsequently completes the hose connection. Such quick connect couplings are particularly desirable when the hose must be connected in a location which is not readily accessible since it eliminates the need for starting the threads and the danger of cross threading. Further, since the body assembly or fixture portion may be threaded into place as a pre-assembly operation, it is easy to insure that the body assembly or fixture portion receives proper torque. Further, the time of assembly and in turn the assembly costs are reduced.
The disconnection of quick connect couplings includes the body assembly or fixture portion having a threaded portion that allows the unscrewing of the body assembly or fixture portion from the machine or fixture to which the hose is attached. The mentioned threaded portion being between separable portions of the body assembly. Upon unthreading the threaded portion, one part of the body assembly remains with the machine or fixture. The other part separates from the first part and remains with the hose connection portion. In either instance, while connection is a quick single stroke process, the disconnection requires a slower unthreading process to provide the opportunity to discover that the fitting is under internal pressure before being completely disconnected. Reconnection is effected, from this point forward, by the inverse of the disconnection process.
Quick connect couplings provide means to seal between the hose stem portion and the body assembly or fixture portion and to provide a mechanical locking of the hose stem portion in the body assembly or fixture portion. To achieve maximum benefit from a quick connect coupling, such coupling must allow substantial tolerance in axial and lateral misalignment of the hose stem portion in relation to the body assembly portion when the process of connection is first begun. Such tolerance facilitates effective connection even when minimum time or minimum access is available during the connection process. Still, the hose stem portion must seat securely upon completion of connection, and should result in a stable and durable connection. If stability is inadequate, movement between the hose stem portion and the body assembly portion leads to excessive wear of the interior of the coupling and premature failure, particularly of the sealing elements. Heretofore, quick connect couplings have merely represented a trade-off between being forgiving of such misalignment and being stable and durable. Couplings with high levels of stability tend to be less forgiving of such misalignment. Forgiving couplings tend to lack stability.
Accordingly, there is a continuing need for a hose coupling that achieves both characteristics of being forgiving of axial and lateral misalignment, at the beginning of connection, and highly stable to enhance durability.